A) Field of the Invention
The present invention relates to a defect inspection method and apparatus for semiconductor wafers subjected to various processes.
B) Description of the Related Art
JP-A-2002-303587 discloses a surface inspection method by which a surface of a wiring pattern on an uppermost layer is scanned with a laser beam and an intensity of reflected or scattered light is compared with a threshold value to inspect defects such as attachment of foreign matters.
JP-A-2002-267625 discloses a defect inspection method by which image data of two different chips on a semiconductor wafer is compared to extract defects based on a difference between image data. This method judges as a defect a region having a luminance difference between image data of two chips equal to or larger than a threshold value.